code: def test_confusion_matrix_add():
      one = plot.ConfusionMatrix.from_raw_data(y_test, y_pred)
      two = plot.ConfusionMatrix.from_raw_data(y_test, y_pred)
      one + two
  
imports: from functools import partial
  import sys
  from unittest.mock import Mock
  import numpy
  from matplotlib.testing.decorators import image_comparison
  from sklearn_evaluation import plot
label_desc: Use image node_id 3 for calling a global function with example usage: test_confusion_matrix_add() without return types